THE INFLUENCE OF DIRECT SUPERVISION OF RESISTANCE TRAINING ON PHYSICAL PERFORMANCE AND HORMONAL RESPONSES.

Abstract

934 This study compared changes in performance, body composition, and hormonal responses after 12 wks of supervised (SUP) or unsupervised (UNSUP), periodized heavy resistance training. Twenty-two, moderately trained men (24±4 yrs) were tested for maximal (1RM) squat and bench press (BP) strength, lower body power output, BP local muscular endurance, body composition, and resting serum [testosterone] and [cortisol] at wk 0, and after 1 and 12 wks of training. Test-retest reliability coefficients were ≥ 0.95. Subjects were randomly assigned (2:1 experimental vs. control) to either SUP (n=14) in which training was supervised by a personal trainer or UNSUP (n=8) in which subjects trained without professional supervision. Groups performed identical linear periodized resistance training programs consisting of preparatory (10-12RM), hypertrophy (8-10RM), strength (5-8RM), and peaking phases (3-6RM) using free-weight and variable-resistance machine exercises. Squat and BP 1RM, mean and peak power output, absolute local muscular endurance, and fat mass increased significantly (p≤0.05) while [cortisol] decreased significantly in both groups following training. FFM,% body fat, and testosterone to cortisol ratio (T/C) increased significantly in SUP following training. Change(Wk 0 to Wk 12) in squat and BP 1RM, absolute local muscular endurance, and FFM were significantly greater in SUP than UNSUP. During training, mean resistance (kg/set) was significantly greater in SUP than UNSUP at wks 8 and 10 for the squat, and wks 7 to 12 for BP. Results indicate that maximal strength, absolute local muscular endurance, FFM, and T/C increase significantly greater following 12 wks of periodized heavy resistance training supervised by a personal trainer than in unsupervised training.